Thread-cutter for sewing-machines.



V J VAN HORN.

YHREAD CUTTER FOR SEWING IVIACHINl-IS. APPLICATION FILED APR. 14, I908. 4 Lflfi ww Patented m 6, 1915.

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THREAD CUTTER FOR SEWlNG MACHINES.

APPLICATION FILED APR. I4. I908. L15 Patented July 6,1915.

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1% 11 wow V, J. VAN HORN.

THREAD CUTTER FOR SEWING MACHINES.

APPLICAHON FILED APR. 4, 1908. I 1}, ,l%@ ,figfi Patented July 6, 1915.

3 SHEETS-SHEET 3.

6 L! W W VANDIVER J'. VAN HORN, OF CHICAGO, ILLINOIS, ASSIGNOR TO UNION SPECIAL' MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

THREAD-CUTTER FOR SEWING-MACHINES.

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Specificationof Letters Patent.

Patented lluly 6, 1915.,

Application filed April 14, 1908. Serial No. 427.029.

To all whom it may concern.

Be it known that. I, VANDIVER J. Van HORN, a citizen of the United States, residing at Chicago, in the county of Cook, State of lllinois, have invented certain new and useful Improvements in Thread-Cutters for Sewing-lilachines, ot' which the followlng 1s a description, reference being had to the accompanying drawing, and to the letters and figures of reference marked thereon.

My invention relates to new and useful improvements in thread cutters for sewing machines, and while I have herein shown my thread cutter as applied to a zigzag stltch- "ing machine, it is evident that said thread cutter may be used in connection with various types of sewing machines.

An ob 'ect of my invention is to provide a thread cutter for a sewing machine which is 'so arranged and operated that the thread cut.

A further object of my invention is to provide means for drawing the thread through the eye of the needle 'to provide a quantity of thread between the eye of the needle and the material, and then to cut the thread close to the surface of the material.

A. further object of my invention is to provide a thread cutter with means for operating the same, and means for preventing its operation except when the needle is well above the material.

A still further object of my invention is to provide a thread cutter with means for operating the same, including a cutter reciprocating across the path of the needle and also providing means for preventing the operation of the machine, when the cutter is in the path of the needle. v

A. still further object of my invention is to provide a. thread cutter operating across the path of the needle, and means for positively withdrawing the thread cutter by the needle the operating mechanism therefor.

operating means, so that said needle cannot he accidentally caused to strike the cutter.

Further objects of my invention will in part be obvious, and will in part be more fully hereinafter described.

In the drawings which show by way of illustration, one embodiment of my inven tion: Figure 1 is av side view of a sewing machine with my thread cutter applied thereto. Fig. 2 is a detail perspective view of the thread cutter and tension release and Fig. 3 is a perspective view of the thread cutter with the parts-positioned for cutting the thread. Fig. 4 is a sectional detail view of the pull off device, operated in connection with the cutter. Fig. 5 is a sectional view showing the position of the needlethread at the time it is cut. Fig. 6 is a detail view showing the operating parts for the cutter when the cutter is across'the path of the needle. Fig. 7 is a detail view showing the presser foot in raised position. Fig. 8 is a similar view from the other side.

In the present embodiment of my invention, I have shown a sewinginachine which comprises a work support 1', an overhanging arm 2, a needle lever 3, which is pivoted at 4 to the overhanging arm, and is reciprocated by a link 5 from the main shaft 6, by the usual belt Wheel 7. Said lever 3 is connected by means of a. link 8 to the needle bar 9, which carries a needle 10:11; the lower end thereof. Said needle bar 9 is -mounted to reciprocate in a needle gate-11 pivoted in the usual manner, so that said needle bar may be vibrated laterally for the purpose of forming zigzag stitches. Said needle gate 11 is connected to a rock shaftlQ which is vibrated by a pivot fork 13. These parts are of the usual construction and will not need further description in this'connection. 'It should be clearly understood, however,

' overhanging arm ;of the machine.

The needle thread is led from the supply between tension disks 16-and 17 mounted on a stud 18 and a spring 19 presses said tension disks 16 and 17 together. this creating the desired tension on the needle thread. The needle thread is led from the tension disks 16 and 17 to a thread eye 20 on the needle lever and thence to a controller 21 which is controlled by the presser foot in the usual manner in this type of machine. The thread is then passed through an eyelet 22 carried by the needle lever from which it is led to an eyelet 23 at the upper end of the needle bar. The presser foot 21 of the machine is carried by a presser bar 25 in the usual manner. Said presser foot 24, is provided with the usual needle slot 26.

.My improved thread cutterconsists of a .cutting blade 27 which is mounted on the upper side of the presser foot in the present 1 illustrated embodiment of my invention, and

is adapted to be reciprocated across the needle slot 26." As a means for guiding the cutter 27. I have provided my presser foot with a guide plate shield 28 which is secured to the upper surface of the presser foot by means of a screw.29 and a pin 30 which passes through an opening in the forward end of the plate 28. Said plate 28, is provided with a slot which registers with the needle slot 26. At the forward end Said plate 28 is bent around underneath the for ward end .of the upturned portion of the presser foot 24. The upper surface of the presser footis recessed to form a guideway for the cutting blade 27 and the plate 28 closes the upper side of said recess.

The cutting blade 27 is provided with a rearwardly extending shank 31. which is .pivotally connected to the forked end of a pivotal support, I have provided said sleeve with a forwardly projecting arm 36 which engages a suitable opening 37 in the lower end of a sliding bar 38. Said sliding bar 38 is Inou'nted'in a guide-way formed in the As said ba r 38-' slides up and down in its guide-way,

f-the cutter will therefore be reciprocated across the path of the needle. The loose'connection between the sliding bar 38 and the arm 36 of the cutter operating sleeve allows the sliding bar 38 to move in a right line.

In'order to pull through the eye of the needle a certain amount of thread so that when the thread is cut, a sufiicient' length of thread is left-through the eye of the needle that the stitching may properly commence, I have provided the following means: A

thread loop 39 is arranged so as to normally encircle the path of the needle and therefore the thread running from the needle eye to the stitching point, will pass through said thread loop.

The thread loop as shown in the present embodiment of my invention is formed of wire which is triangular in shape, and which is pivoted at 40 .to a sliding bar 41. A spring 12 operates upon said thread loop 35) and normally presses the same toward the rear of the machine. A stop shoulder 43 carried by said thread loop engages a projection it on the sliding bar 41. and limits the rearward movement of said thread loop. The sliding bar 41 is provided with a shank 15 which extends up into a supporting sleeve 46. The sleeve 46 is formed with a contracted opening at its lower end, which serves as a stop and the shank 4-5 is provided with an enlarged head 17. which engages the stop and thus limits the downward movement of the shank 45 and the bar 41, relative to the sleeve 46. spring 48 located within the sleeve 46. engages the enlarged head 4-7 at one end, and a closing screw 19 at the other end. and normally forces the barfll and the thread loop in a,downward direction. relative to the sleeve 46. Said sleeve 46 is also provided with a downwardly extending lip 50 which serves as a guide for the bar 41, and also serves as a means for preventing oscillations of said bar '41, and the thread loop 39. The sleeve 46 is carried by a sliding bar 51 which is slotted and provided with a guiding screw or screws 52 so that said bar may slide vertically carrying with it the sleeve 16 and the threadloop 39. Thesliding bar 51 is connected by a link 53 to a lever 5% pivoted at 55 to the overhanging arm. Said lever 54 is also provided with a downwardly extending curved arm 56. As a means for oscillating the arm 54, I have provided a rock shaft 57 which is mounted in a bearing block 58, supported by the overhanging arm. Said rockshaft 57 is provided with an arm which extends downwardly and normally rests in contact with the downwardly extending arm 56 of the lever 54. The rock shaft 57 is also provided with an arm 50 which may be suitably connected with an operating treadle or knee shift. It will be obvious therefore, that as the rock shaft 57 is oscillated. the arm 59 will bear against the arm56 and thus oscillate the arm 54 which in turn willrecip- -rocate the bar 51 and the sleeve 46. carried thereby and thus give to the thread loop 39 a reciprocation. The spring 61 engages the lever 54 at 62. and a suitable stud 63 on the arm of the machine. and normally tends to hold the forward end of the lever 5:4. in its .lowered position. The sleeve 46 is connected to a block 65 which is connected by means of screws to the lower end of the sliding bar 51. Said block 65at its upper end is provided with a contact shoulder 66, projecting into the slotted portion of the bar 51. The sliding bar 38 which operates the cutter blade is located directly in rear of the sliding bar 51 and is provided with a shoulder 67 near its lower end, which is located in the path of movement of the lower end of the sliding bar 51. The upper end of the sliding bar 38 is provided with a forwardly projecting lug 68 which extends into the slot in the sliding bar 51, and is located in the path of the contact shoulder 66. The shoulder 67 and the lug 68 are spaced so that the sliding bar 51 has considerable,range of movement before the sliding bar 38 willbe operated.

The operation of my device is as follows :The spring 61 normally holds the lever 54swith its forward end lowered and with the sliding bar 51 thrown down. so as to contact with the shoulder 67 throwing down also the sliding bar 38. .In this position of the parts, the thread loop as shown in Fig. 2 is in its forward position encircling the path of the needle and the needle thread extends from the eye of the needle through said thread loop to the material. The arm '38 of the sleeve 33, is in its lower position and the cutter blade therefor, retracted. The operator now oscillates the rock shaft 57, which in .turn oscillates the lever 54, moving up the slide 51. In the first'upward movement of the sliding bar 51 there will be no movement imparted to the cutter blade. As the bar 41 carrying the thread loop moves upward, the spring 42 will cause the thread loop which was resting on the presser foot, to move toward the rear of the machine, and cross the path of the needle carrying with it the needle thread. A further movement of the sliding bar 51' carries the thread loop up in rear of the needle to a position considerably above the eye of the needle, which will pullthread through the eye of the needle. Just before thesliding bar 51 reaches its extreme upper position,

the contact shoulder 66 strikes the lug 68 and operates the sliding bar 38, which in turn forces the cutter blade across the thread slot in the presser. foot, and cuts-the needle thread close to the material. When the rock shaft 57 is released by the operator, the spring 61 throws down the forward end of the lever 54 and the sliding bar 51 is lowered, carrying the thread loop 59 downward to the position shown in Fig. 2. The sliding bar 51 in its downward movement strikes the shoulder 67 and forcing down the arm 36 positively withdraws the cutter blade.

As a means for releasing the tension=on the needle thread, so that the needle thread may readily be drawn through the eye of the needle, I have provided the rock shaft 57 with a pivoted tension releasing arm 69,

which is pivoted at 70 to the arm 59. The upper end of the tension releasing arm extends to a position adjacent the tension disks 16, 17, so that when the arm 69 is oscillated, the upper end thereof is crowded between the tension disk separating the same, so as to relieve the tension on the needle thread. The lower end of the arm 69 is provided with a stop screw 71, engaging the lower-end of the arm 59. Said arm 69 at its lower end is provided with a laterally projecting portion 72 which carries an adjustable screw 73 located so as to contact with the standard of the machine. I As the rock shaft 57 is oscillated, the pivotal point of the arm 69 is carried forward and the stop screw 73 is brought into contact with the standard 101 the machine, and this throws the upper end of the arm 69 forward between the tension disks. A spring 74. carried by the rock shaft 57, engages the arm 69 below the pivotal point 70, and normally throws the u perend of said arm away from the tension disks.

The screw 71 limits the outward movement of the upper end of the arm 69. I vhave provided the needle lever 3, with a stop ried down so as to be out of the path of the lower end of the arm 56, as shown in Figs. 1 and The operator may now oscillate the rock shaft 57 and operate the thread cutter. that the same will be struck by the cutter blade, if the thread cutter were operated, the stop block 75 is carried up into the path of the arm 56, so that the thread cutter can not be operated. If the needle is in raised position and the cutter blade operated and for some reason the machine should be started, the stop block 75 will immediately strike the arm 56 and throw the lever 54 so as to positively throw the cutter blade from across "the path of' the needle. It will be seen therefore, that I have provided mechanism whereby the thread cutter can only be operated'when the needle is at its extreme upper position, and furthermore, ifthe machine should be accidentally started with the cutter blade across the needle slot, the machine. itself, will automatically operate to withdraw the cutter.

, When the cutter blade is withdrawn from across the needle slot, and the thread loop presser foot may be raised as the bar 32 readily slides up into said sleeve. The shank 4:5 for supporting the thread loop 39,

If, however, the needle is down so &

may also readily slide up into the sleeve 46 compressing the spring 48 so that it will readily be seen that the presser foot may at any time be raised orclowered without disturbing the position of the thread cutter or' the thread loop or the operating parts therethread as above noted, exte nds down around the looper. If therefore, the material is withdrawn from the machine after the needle thread is cut, the looper will operate to pull the end of the needle thread down through the material to the lower side thereof, which will serve to lock the threads and prevent unraveling. It will therefore, be seen that my invention contemplates not only the cutting'of the needle thread,.but th drawing of the same to the'under side of the material, whereby the desired locking of the threads is secured. t

It will be noted that the tension releasing arm 69 moves almost entirely through the tension device as shown in Fig. 6.. The result of this movement is, that the thread will be first released so as to be readily pulled through the tension by the thread loop and after the arm reaches the opposite side of the tension disks, they will tilt, and close on the thread on the right hand side as viewed in -Fig. 6. This grippingof the thread will cause the thread loop on the last part of its movement to pull the thread up tight. It

- will also be noted that the spring 61 operates to automatically return the parts to normal position, as soon as the arm is released.

It. will be obvious that my thread cutter may be operated by mechanical means controlled manually and that many changes may be made in the details of construction or arrangement of parts without departing from the spirit of my invention. -Ha-ving thus particularly descnbed my invention, what I claim as new and desire to secure by Letters Patent is A sewing-machine including in combination, a needle, a thread cutter, manuallyoperated means for operating said thread cutter and means for preventing the operation of said manually operated means, except when the needle is above the material and out of the path of said thread cutter.

. 2. A sewing machine including in combination, a needle, a thread cutting blade, manually-operated means for reciprocating the same across the path of the needle, and means for preventing the operation of said blade reciprocating means except when the needle is out of the path of said cutting blade.

3. A sewing machine including in combination, a presser foot, means for lifting the presser foot, a needle, means for engaging the needle thread between the eye of the needle and the material for pulling thread through the eye of the needle, means above the material for cutting the needle thread at a point adjacent the material, and means for preventing the operation of said cutting means except when the needle is raised above the material.

4. A sewing machine including in combination, a presser foot, means for raising the presser foot, a needle, a thread cutting blade moving across the path of the needle above the material, means operating to pull thread through the eye of the needle and subsequently cut the thread at a point adjacent the material, and means for preventing the operation ofthe thread-cutting blade except when the needle is above said blade.

5. A sewing machine including in combination, a needle, a thread-cutting blade moving across the path of the needle above the material, means for pulling thread through the eye of the needle and for subsequently operating said cuttin blade to cut the .thread at a point ad acent the material, means for preventing the operation of the cutting blade ,except when the needle is above said blade, and means for pulling the end of the cut thread through the material.

6. A sewing machine including in combination, a needle, a presser foot mechanism and means for lifting the same, a tension device, and manually operated mechanism for first releasing the tension on the needle thread, then pulling thread through the eye of the needle, and then cutting the thread at a point above and adjacent the material before the presser foot is lifted.

'TA sewing machine including in combination, a needle, a tension device, and manually operated mechanism for first releasing the tension on the needle thread, then pulling thread through the eye of the needle, and then cutting the thread at a point above and adjacent the material, and means for pulling the end of the cut thread through the material.

8. The combination of a needle, a-thre'ad cutter, and means for through the eye of the needle prior to the cutting of the thread, including a thread loop surrounding the path of the needle.

9. The combination of a needle, a thread cutter, and means for pulling thread through the eye of the needle prior to the cutting of the thread, including a. slide, a pivoted thread loop carried thereby, and surrounding the thread leading from the eye of the needle to the material.

10. The combination of a needle, a thread pulling thread' intense cutter, and means for pulling thread through the eye of the needle prior to the cutting of the thread, including a slide, a sleeve carried thereby, a bar having a sliding connection with said sleeve, and a thread loop carried by said bar and adapted to engage the thread between the eye of the needle and the material.

11. The combination of a needle, a thread cutter, and means for pulling thread through the eye of the needle prior to the cutting of the thread,'including a sliding bar, a sleeve carried-thereby, a bar having a shank sliding in said sleeve, a guide plate for preventing oscillation of said bar, and means for engaging the needle thread between the eye of the needle and the material supported by said bar.

12. The combination of a needle, a thread cutter, and means for pulling thread through the eye of the needle prior to the cutting, of the thread including a sliding bar, a sleeve carried, thereby, a bar having a shank sliding in said sleeve, a guide plate for preventing oscillation of said bar, a

thread loop pivoted to said bar, a spring operating to turn said thread loop about its pivot and stops for limiting the movement of said thread 1001)..

' 13. A sewing machine including in combination, a needle, a presser foot, a thread cutting blade guided by said presser foot, manually-operated means for reciprocating said thread cutting blade across the path of the needle, and means for preventing the operation of said blade except when said needle is at the upper end of its stroke.

14. A sewing machine including in combination, a main shaft, a needle, means actuated by said main shaft for reciprocating said needle, a thread cutting device, means for moving said device across the path of the needle to cut the needle thread, and means operated bythe needle actuating means for positively Withdrawing the thread cutting device from the path of the needle on the first part of the downward movement of the needle and before the needle reaches the cutting device.

15. A sewing machine including in combination, a needle, means for operating the same, a thread cutter, manually controlled means for operating the cutter and means operated by said needle operating means for preventing the operation of said manual means, except when the needle is at the upper end of its stroke.

16. The combination of a presser foot, a thread cutting blade supported by said presser foot, means carried by the head of the machine for reciprocating s'aid thread cutting blade, said means including a sliding connection, whereby the presser foot may be lifted, when desired without operating the cutting blade.

17 The combination of a presser foot, a cutter blade supported by said presser foot, means for operating said cutter blade ineluding a sleeve pivoted to the head of the machine and having a sliding connection with said cutter blade, whereby said presser foot 'may be lifted when desired without operating the cutting blade.

18. The combination of a thread cutter and means for operating the same, including a vertically arranged sleeve, a horizontal pivotal support for attaching said sleeve to the head of the machine, means for oscil lating the sleeve, and means having a sliding engagement with the sleeve and connected to the thread cutter, for operating the same when the sleeve is oscillated.

19. The combination of a thread cutter including a cutting blade and means for operating said blade, including a vertically arranged sleeve pivoted to the head of the machine, a bar sliding in said sleeve and having a pivotal connection with the cutting blade, an arm extending laterally from said sleeve, and means engaging said arm for oscillating the sleeve to operate the cutter.

20. The combination of a. presser foot having a recess in its upper face, a cutter blade mounted therein, means for reciprocating said cutter blade, and a plate secured to the upper face of said presser foot, and holding said cutter blade in its guiding re 'cess.

21. A sewing machine including in combination a work" support, a needle, a looper cooperating with said needle beneath the work support, a thread cutter operating to cut the needle thread above the material,

means for operating the thread cutter, and

means for preventing the operation of the thread cutter, except when the needle is raised and the looper is forward in the needle thread loop.

22. The combination of a needle, a ten sion device for the needle thread, means for pulling thread through the eye of the needle, said means including a rock shaft, an arm pivoted to said rock shaft, and operating to release the tension, an adjust able screw carried by said arm, and a stop coiiperating with said adjustable screw.

23. The combination of a tension device,

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with means for releasing the tension, including a rock shaft, an arm carried thereby, and operating to release the tension, a spring for throwing said arm in one direction, a stop screw for limiting the movement of said arm, and an adjustable screw and cooperating stop, for causing the movement of said arm, when said-rock shaft is oscillated.

24. The combination of a thread cutter including a cutting blade, a slide for operating said cutting blade, said slide being provided with spaced lugs, a second slide having contacting shoulders for engaging said lugs, said lugs being spaced a greater distance than the contacting shoulders,

whereby the second slide, may have a limited movement before operating said first named slide, and a thread pull off, operated by said second named slide.

25. The combination of a needle, and means for pulling thread through the eye of the needle, including a reciprocating member, a thread loop carried thereby, and

adapted to engage the needle thread, be-

the thread, including a slide, a pivoted thread loop carried thereby and surrounding the thread leading from the eye of the needle to the material, said thread loop being spring pressed.

27. A sewingmachine including in combination, stitch forming mechanism having a-vneedle, a thread cutter,ha\'ing a cutting blade reciprocating across the path of the needle means for drawing thread through the eye of the needle and means :for preventing the operation of the stitch forming mechanism, while said cutter blade is in the path of the needle.

In testimony whereof I affix my signature, in presence of two witnesses.

VANDIVER J. VAN HORN. Witnesses:

CHESTER MGNEIL, A. B. CLOTHIER. 

